package cn.org.eshow.util;
/**
 * 
 * @author leida
 *
 */
public class Escape {

	private final static String[] hex = { "00", "01", "02", "03", "04", "05", "06", "07", "08",
			"09", "0A", "0B", "0C", "0D", "0E", "0F", "10", "11", "12", "13", "14", "15", "16",
			"17", "18", "19", "1A", "1B", "1C", "1D", "1E", "1F", "20", "21", "22", "23", "24",
			"25", "26", "27", "28", "29", "2A", "2B", "2C", "2D", "2E", "2F", "30", "31", "32",
			"33", "34", "35", "36", "37", "38", "39", "3A", "3B", "3C", "3D", "3E", "3F", "40",
			"41", "42", "43", "44", "45", "46", "47", "48", "49", "4A", "4B", "4C", "4D", "4E",
			"4F", "50", "51", "52", "53", "54", "55", "56", "57", "58", "59", "5A", "5B", "5C",
			"5D", "5E", "5F", "60", "61", "62", "63", "64", "65", "66", "67", "68", "69", "6A",
			"6B", "6C", "6D", "6E", "6F", "70", "71", "72", "73", "74", "75", "76", "77", "78",
			"79", "7A", "7B", "7C", "7D", "7E", "7F", "80", "81", "82", "83", "84", "85", "86",
			"87", "88", "89", "8A", "8B", "8C", "8D", "8E", "8F", "90", "91", "92", "93", "94",
			"95", "96", "97", "98", "99", "9A", "9B", "9C", "9D", "9E", "9F", "A0", "A1", "A2",
			"A3", "A4", "A5", "A6", "A7", "A8", "A9", "AA", "AB", "AC", "AD", "AE", "AF", "B0",
			"B1", "B2", "B3", "B4", "B5", "B6", "B7", "B8", "B9", "BA", "BB", "BC", "BD", "BE",
			"BF", "C0", "C1", "C2", "C3", "C4", "C5", "C6", "C7", "C8", "C9", "CA", "CB", "CC",
			"CD", "CE", "CF", "D0", "D1", "D2", "D3", "D4", "D5", "D6", "D7", "D8", "D9", "DA",
			"DB", "DC", "DD", "DE", "DF", "E0", "E1", "E2", "E3", "E4", "E5", "E6", "E7", "E8",
			"E9", "EA", "EB", "EC", "ED", "EE", "EF", "F0", "F1", "F2", "F3", "F4", "F5", "F6",
			"F7", "F8", "F9", "FA", "FB", "FC", "FD", "FE", "FF" };
	private final static byte[] val = { 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x00, 0x01, 0x02, 0x03,
			0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x0A,
			0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
			0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F };

	public static String escape(String s) {
		StringBuffer sbuf = new StringBuffer();
		int len = s.length();
		for (int i = 0; i < len; i++) {
			int ch = s.charAt(i);
			if (ch == ' ') { // space : map to '+'
				sbuf.append('+');
			}
			else if ('A' <= ch && ch <= 'Z') { // 'A'..'Z' : as it was
				sbuf.append((char) ch);
			}
			else if ('a' <= ch && ch <= 'z') { // 'a'..'z' : as it was
				sbuf.append((char) ch);
			}
			else if ('0' <= ch && ch <= '9') { // '0'..'9' : as it was
				sbuf.append((char) ch);
			}
			else if (ch == '-'
					|| ch == '_' // unreserved : as it was
					|| ch == '.' || ch == '!' || ch == '~' || ch == '*' || ch == '\'' || ch == '('
					|| ch == ')') {
				sbuf.append((char) ch);
			}
			else if (ch <= 0x007F) { // other ASCII : map to %XX
				sbuf.append('%');
				sbuf.append(hex[ch]);
			}
			else { // unicode : map to %uXXXX
				sbuf.append('%');
				sbuf.append('u');
				sbuf.append(hex[(ch >>> 8)]);
				sbuf.append(hex[(0x00FF & ch)]);
			}
		}
		return sbuf.toString();
	}

	public static String unescape(String s) {
		StringBuffer sbuf = new StringBuffer();
		int i = 0;
		int len = s.length();
		while (i < len) {
			int ch = s.charAt(i);
			if (ch == '+') { // + : map to ' '
				sbuf.append(' ');
			}
			else if ('A' <= ch && ch <= 'Z') { // 'A'..'Z' : as it was
				sbuf.append((char) ch);
			}
			else if ('a' <= ch && ch <= 'z') { // 'a'..'z' : as it was
				sbuf.append((char) ch);
			}
			else if ('0' <= ch && ch <= '9') { // '0'..'9' : as it was
				sbuf.append((char) ch);
			}
			else if (ch == '-'
					|| ch == '_' // unreserved : as it was
					|| ch == '.' || ch == '!' || ch == '~' || ch == '*' || ch == '\'' || ch == '('
					|| ch == ')') {
				sbuf.append((char) ch);
			}
			else if (ch == '%') {
				int cint = 0;
				if ('u' != s.charAt(i + 1)) { // %XX : map to ascii(XX)
					cint = (cint << 4) | val[s.charAt(i + 1)];
					cint = (cint << 4) | val[s.charAt(i + 2)];
					i += 2;
				}
				else { // %uXXXX : map to unicode(XXXX)
					cint = (cint << 4) | val[s.charAt(i + 2)];
					cint = (cint << 4) | val[s.charAt(i + 3)];
					cint = (cint << 4) | val[s.charAt(i + 4)];
					cint = (cint << 4) | val[s.charAt(i + 5)];
					i += 5;
				}
				sbuf.append((char) cint);
			}
			i++;
		}
		return sbuf.toString();
	}

}
